French fries vs. baked potatoes: New study reveals one raises diabetes risk by 20%

08/13/2025 / By Ava Grace

French fries (eaten 3+ times weekly) increase Type 2 diabetes risk by 20 percent, while baked, boiled or mashed potatoes show no significant risk. Deep-frying creates harmful compounds like acrylamide and adds empty calories.
Though fries have a slightly lower glycemic index due to slowed digestion, their toxic compounds and trans fats outweigh any minor metabolic benefit compared to non-fried potatoes.
Diabetes risk is strongly linked to potato consumption 12–20 years prior to diagnosis, highlighting how poor dietary habits in early adulthood can have delayed consequences.
The fry-diabetes connection is strongest in people with higher BMIs and white participants, compounded by associated unhealthy diets (e.g., red meat, sugary drinks).
Replacing fries with whole grains reduces diabetes risk by 19%, while baked potatoes are a safer choice than fries or white rice. Moderation and smarter substitutions are key.

For decades, potatoes have been demonized as a carb-heavy dietary villain, blamed for weight gain and blood sugar spikes. But new research suggests the real culprit isn’t the humble spud itself; it’s how people prepare it.

A groundbreaking Harvard University study reveals that eating french fries just three times a week may increase Type 2 diabetes (T2D) risk by a staggering 20 percent. Meanwhile, baked, boiled or mashed potatoes show no such danger. The findings challenge long-held assumptions about nutrition, forcing Americans to reconsider what’s really on their plates.

For 30 years, Harvard researchers tracked the diets of more than 205,000 U.S. adults, analyzing how different potato preparations impacted long-term health. The results were striking: Every three servings of french fries per week raised diabetes risk by 20 percent, while non-fried potatoes had no significant effect.

The study published Aug. 6 in The BMJ, confirms that not all potatoes are created equal. Deep-frying transforms them from a simple starch into a metabolic time bomb. (Related: Defaulting to french fries could fry your health: How America’s favorite side dish is fueling a diabetes crisis.)

The science is clear – french fries aren’t just potatoes, they’re a chemical and caloric disaster. Deep-frying at high temperatures produces acrylamide, a toxic compound linked to inflammation and insulin resistance.

Deep-frying also strips away resistant starches, replacing them with trans fats and excessive oil, which further disrupt blood sugar control. Registered dietitian Melissa Mitri, who was not involved in the study, notes that fries are “much higher in calories than baked or mashed potatoes.”

The glycemic index factor: Why fries are the real problem

Potatoes naturally have a high glycemic index (GI), meaning they can cause rapid blood sugar spikes. But preparation matters: Boiled or mashed potatoes digest quickly, raising glucose levels fast.

Surprisingly, fries – despite their fat content – have a slightly lower GI due to the crispy outer layer slowing digestion. Yet the trade-off isn’t worth it. The harmful compounds and empty calories far outweigh any minor metabolic benefit.

Perhaps the most alarming finding? The damage takes decades to surface. The study found that potato consumption 12 to 20 years before a diabetes diagnosis had the strongest link to risk. Type 2 diabetes doesn’t develop overnight – it’s a slow burn of insulin resistance fueled by years of poor eating habits.

The study adjusted for genetics, exercise and overall diet – yet the fry-diabetes connection remained strongest in two groups: People with higher BMIs and White participants. Excess weight exacerbates insulin resistance, meaning those already struggling with obesity face even greater danger from frequent fry consumption. Worse, fry lovers tended to eat more red meat, sugary drinks and processed foods – compounding the risk.

The good news? Small changes make a big difference. Replacing fries with whole grains (like farro or whole-wheat pasta) slashed diabetes risk by 19 percent.

Even swapping baked potatoes for whole grains reduced risk by four percent. The only bad trade came in the form of white rice, which increased risk by three percent due to its lack of fiber and rapid digestion.

This study isn’t about banning fries; it’s about informed choices. In an era where Big Food pushes processed junk, individuals must take ownership of their health. Potatoes aren’t evil, but drowning them in oil and salt is a recipe for disaster.

Watch this video about what goes into fast food fries.

This video is from the Natural Cures channel on Brighteon.com.